1. Field of the Invention
The present invention relates to technology for analyzing a communication network.
2. Description of the Related Art
A mobile core network of a mobile phone service provider is configured from a plurality of network devices. In addition, a mobile phone terminal of a subscriber of a mobile phone service transmits and receives packet data with an external network such as the Internet via the plurality of devices. In addition, when service quality degradation occurs, the mobile phone service provider locates an occurrence portion of the quality degradation and engages in improvement of a sensory quality of communication of the subscriber and accident prevention.
As first technology for locating a service quality degradation, there is a method of analyzing the scale of the number of quality degraded terminals.
In Japanese Patent No. 5,239,749, a method of determining the scale of the number of quality degraded terminals as the large scale when a terminal failure rate is equal to or larger than a predetermined threshold value and estimating a failure of a network device to relay communication of mobile terminals and a communication detection device detecting the communication in a communication area or a relay line to relay the communication as a factor of the quality degradation is disclosed as the method of analyzing the scale of the number of quality degraded terminals.
In addition, as second technology for locating a service quality degradation, there is a method of visualizing a call flow mainly when the quality degradation is detected. In this method, messages of control planes transmitted and received between network devices to relay the communication are collected and a message associated with a quality degraded terminal is extracted and visualized at the time of detecting the quality degradation of a service.
In “JDSU LTE Network End-to-End Test Solutions”, [online], JDSU, [Oct. 28, 2014 search], Internet (URL: http://www.jdsu.com/productliterature/lte-network-br-nsd-tm-ae.pdf), an example of a method of the detection and the visualization is described. In a system described in “JDSU LTE Network End-to-End Test Solutions”, [online], JDSU, [Oct. 28, 2014 search], Internet (URL: http://www.jdsu.com/productliterature/lte-network-br-nsd-tm-ae.pdf), for example, a service provider defines a combination of a plurality of Key Performance indexes (KPI) as a quality degradation index in advance and visualizes a communication failed call flow.